Cardiac muscle
It is only found in the heart, and cardiac contractions pump blood throughout
the body and maintain blood pressure. Like skeletal muscle, cardiac muscle is
striated, but unlike skeletal muscle, cardiac muscle cannot be consciously
controlled and is called involuntary muscle. It has one nucleus per cell, is
branched, and is distinguished by the presence of intercalated disk.
Smooth muscle
Located in various internal structures including the digestive tract, uterus and
blood vessels such as arteries. Smooth muscle is arranged in layered sheets that
contract in waves along the length of the structure. Another common term is
involuntary muscle, since the motion of smooth muscle happens without our
conscious awareness.
Functional Characteristics / Basic Properties of Muscle
Tissue]
Excitability (Irritability)
• It is the ability to respond to a stimulus, which may be delivered from a motor
neuron or a hormone.
Contractility
• It is the ability of muscle cells to forcefully shorten. Contractility allows muscle
tissue to pull on its attachment points and shorten with force.( muscles can only
pull, never push.)
Extensibility
• It is the ability of a muscle to be stretched or extended.
Elasticity
• The ability to return to its original shape after being stretched or contracted.
Muscle Functions
Produce movement
❑ All movements of the human body are produced by muscles.
Maintain posture
❑ Some muscles are in a partial state of contraction at all times.
Stabilize joints
❑ Muscle tendons reinforce and stabilize joints
Generate heat
❑ ¾ of the energy used to contract muscles is lost as heat. Needed to maintain
body temperature
PHYSIOLOGY OF SKELETAL MUSCLE
• Regulation of skeletal muscle cell/fiber contraction involves:
1. Generation and transmission of an action potential (electrical
current) along the sarcolemma
2. Excitation-contraction coupling
• Skeletal muscle cells are stimulated by motor neurons. The axon of each motor neuron
divides profusely as it enters the muscle
• Each axonal ending forms a branching neuromuscular junction with a single muscle fiber.
• An end plate potential is set up when neurotransmitter acetycholine (ACh) released by a
nerve ending binds to Ach receptors on the sarcolemma, causing changes in membrane
permeability that allow ion flows that deplolarize the membrane at the motor end plate.
• In excitation-contraction coupling, the action potential is propagated down the T tubules,
causing calcium to be released from the SR into the cell interior.
• Sliding of the filaments is triggered by rise in intracellular calcium ion level.
• Troponin binding of calcium moves tropomyosin away from myosin binding sites on actin,
allowing cross bridge.
• Myosin ATPases split ATP, which energizes the working strokes and is necessary for bridge
detachment.
• Cross bridge activity ends when calcium is pumped back into the SR.
CONTRACTION of a SKELETAL MUSCLE
A motor unit is one motor neuron and all the muscle cells it innervates
• The neuron’s axon has several branches, each of which forms a
neuromuscular junction with one muscle cell
• The respond of a motor unit to a single action potential of its motor
neuron is called a muscle twitch
• Isotonic contractions occur when the muscle shortens (concentric
contraction) or lengthens (eccentric contraction) as the load is moved
• Isometric contractions occur when muscle tension produces but the
muscle does not shorten or lengthen
ACTION & INTERACTIONS OF SKELETAL MUSCLES IN THE BODY
➢ Skeletal muscles are arranged in opposing groups across body
joints so that one group can reverse or modify the action of the
other.
TYPES OF SKELETAL MUSCLE ACTION
AGONIST ➢ A muscle that is primarily ATTACHMENT OF MUSCLE
responsible for producing a
(biceps brachii) movement . 1. ORIGIN (proximal & fixed)
➢ The end of a muscle attached
ANTAGONIST ➢ A muscle that opposes or to the bone that does not
reverse the movement of a move .
(triceps brachii) prime mover .
2. INSERTION (distal & moves)
SYNERGIST ➢ A muscle that complements ➢ The point of attachment of
the action of a prime mover the muscle on the bone that
(brachialis) (stabilizing joints) . moves .
FIXATOR ➢ A muscle that provides a
stable base for the action of
(muscle that holds the prime mover (when
scapula firmly in synergist function to
place such as immobilize a bone or a
rhomboideus) muscle’s origin) .
ANATOMY
OF
THE HEART
SIZE AND LOCATION
• Cone-shaped
• About the size its of fist
• Located in the center of the thorax (mediastinum)
• Obliquely, with about two third of its bulk to the left of
• the body’s midline
PERICARDIUM
AND WALLS
Lies within a protective sac called the pericardium
a. Fibrous pericardium
b. Serous pericardium
i. Parietal layer
ii. Visceral layer
Pericardial cavity contains lubricating serous fluid
Wall of the heart is composed of:
a. Epicardium (visceral pericardium)
b. Myocardium (cardiac muscle)
c. Endocardium
CHAMBERS&ASSOCI
ATED GREAT
VESSEL
4 chamber:
a. Right atrium
b. Right ventricle
c. Left atrium
d. Left ventricle
2 atrioventricular (AV) valves:
a. Tricuspid valve
b. Bicuspid valve or mitral valve
2 semilunar valves:
a. Pulmonary semilunar valve
b. Aortic semilunar valve
PATHWAY OF BLOOD THROUGH THE HEART
• The heart functions as a double pump
• The right heart is the pulmonary circuit
pump (right heart to lungs to left heart)
• The left heart is the systemic circuit pump
CARDIAC CONDUCTION SYSTEM
Cardiac muslehas a unique abilityto
generate its own electrical signal call
(autoconduction)
4 component
1.sinoatrial (SA) node
2.atrioventricular (AV) node
3.atrioventricular (AV) bundle (bundle of
his)
4.purkinje fiber
TYPE OF BLOOD VESSEL
Blood vessel have 2 system which is Arterial System and Vernous System. Arterial have
three type of blood vessel. One of the type of the vessel is Arteries. Carrying the blood from the
heart is the main purpose of the arteries that bring oxygen-rich blood to your all body cells. Arteries
can be divided into 3 group relative to size and function which is Elastic Arteries, Muscular Arteries
and Asrterioles. Furthermore, Asrterioles is one of the part in arteries. Asrteriolesis a small blood
vessel that sending blood away from your heart, and are connectors between your arteries and
capillaries. They manoeuver your blood pressure and blood flow throughout your body, using their
muscles to change their diameter. Last type of blood vessel in the Arterial System is Capillaries.
Capillaries is the smallest blood vessel. Capillaries is a form to connection between the vessel that
sending blood away from the heart (arteries) and the vessel that return blood to the heart (veins).
The fundamental function of capillaries is the exchange of materials between the blood and tissue
cells.
Second system is Vernous System. Vernous System have 2 type of blood vessel which is
venules and veins. Blood drains from capillaries into venules and have a tiny vein that unite to form
larger venules and veins. Carry blood toward the heart is one of the veins purpose. Veins carrying
deoxygenated blood from the body tissues to the heart, with exception of the pulmonary veins.
Veins also make sure that blood contain paired semilunar valves that permit blood to flow only one
direction, restricting any backflow.
RESPIRATORY PHYSIOLOGY
➢ RESPIRATION
BOTH RESPIRATORY SYSTEM & CARDIOVASCULAR SYSTEM
ARE INVOLVED IN RESPIRATION.
➢ RESPIRATION INVOLVES 4 PROCESSES
1) PULMONARY VENTILATION (BREATHING): MOVEMENTS OF GASES
INTO AND OUT OF THE LUNG
• (INSPIRATION AND EXPIRATION)
2) EXTERNAL REPIRATION (PULMONARY DIFFUSION): GASES
EXCHANGE BETWEEN THE LUNGS AND BLOOD.
• O2 FROM LUNGS (ALVEOLI) DIFFUSES INTO THE BLOOD (LUNG
CAPILLARIES)
• O2 FROM BLOOD (LUNG CAPILLARIES) DIFFUSES INTO LUNGS
(ALVEOLI)
3) TRANSPORT OF RESPIRATORY GASES: O2 & CO2 MUST BE
TRANSPORTED BETWEEN THE LUNGS & TISSUE CELLS OF BODY.
CARDIOVASCULAR SYSTEM WHICH USES BLOOD AS THE TRANSPORT
FLUID.
4) INTERNAL RESPIRATION: EXCHANGE OF GASES IN THE BODY TISSUE
CELLS
• CO2 FROM THE BODY CELLS EXCHANGE FOR O2 FROM THE BLOOD
➢ INSPIRATION (INHALATION)
▪️ RIBS AND STERNUM MOVED BY THE EXTERNAL INTERCOSTALS MUSCLES
▪️ DIAPHRAGM CONTRACTS, FLATTENING DOWN TOWARD THE ABDOMEN (MOVE
INFERIORLY)
▪️ THIS ACTION EXPANDS THE THORACIC CAGE, IN TURN EXPANDING THE LUNGS
▪️ THE AIR WITHIN THEM HAS MORE SPACE TO FILL (THE PRESSURE WITHIN THE
LUNGS DECREASE)
▪️ THE PRESSURE IN THE LUNG IS LESS THAN THE PRESSURE OF THE AT
OUTSIDE THE BODY - AIR RUSHES INTO THE LUNGS TO REDUCE THIS PRESSURE
DIFFERENCE
▪️ FORCE BREATHING/ INSPIRATION:
• THE SCALENES AND STERNOCLEIDOMASTOID IN THE NECK AND THE
PECTORALS IN THE CHEST HELP RAISE THE RIBS EVEN MORE THAN DURING
REGULAR BREATHING
➢ EXPIRATION (EXHALATION)
▪️ DIAPHRAGM RELAXES AND RETURNS TO ITS NORMAL UPWARD POSITION (MOVE
SUPERIORLY)
▪️ EXTERNAL INTERCOSTALS MUSCLE RELAX, THE RIBS AND STERNUM LOWER BACK
INTO THEIR
RESTING POSITIONS
▪️ THE ELASTIC NATURE OF THE LUNG TISSUE CAUSES IT TO RECOIL TO ITS RESTING
SIZE
▪️ THIS INCREASES THE PRESSURE IN THE THORAX - AIR IS FORCED OUT OF THE LUNGS
▪️ FORCE BREATHING/EXPIRATION:
• THE INTERNAL INTERCOSTALS MUSCLES PULL THE RIBS DOWN, ASSISTED BY THE
LATISSIMUS DORSI AND QUADRATUS LUMBORUM MUSCLES
➢ NONRESPIRATORY AIR MOVEMENTS
❖ MOST OF THE AIR MOVEMENTS RESULT FROM REFLEX ACTIVITY,
BUT SOME ARE PRODUCED
▪ VOLUNTARILY
❖ AIR MOVEMENTS:
▪ COUGHING
▪ SNEEZING
▪ CRYING (INVOLVED EMOTIONAL INDUCED MECHANISM)
▪ LAUGHING (INVOLVED EMOTIONAL INDUCED MECHANISM)
▪ YAWNING
▪ SNORIN
▪ HICCUPPING
SITS WHERE BONES
MET
FUNCTION :
To hold bones together
and to allow movement
of the skeleton
ARTICULATIONS
[ JOINTS ]
CLASSSIFICATION 3 FUNTIONAL
CATEGORIES :
OF JOINTS
Synarthroses
1.FIBROUS JOINT (immovable)
Amphiarthroses
The bones united by (slightly movable)
fibrous connective Diarthroses
tissue (freely movable)
No joint cavity
Usually synarthroses
[immovable] or
synarthrotic
Types :
- Sutures [skull]
- Syndesmoses
[tibia,fibula]
- Gomphoses [tooth]
2. CATILAGINOUS JOINTS
The bones are united by a plate of hyelin
cartilage or fibrocartilage
No joint cavity
Usually amphiarthroses [slightly movable]
or amphiarthrotic
Types :
- Synchondrosis : synarthrotic [epiphyseal
plate and costal cartilage]
- Symphysis : amphiarthrotic [pubic
symphysis]
3. SYNOVIAL JOINTS
Bones move easily on each other
Ends of the bones are plated with a smooth
articular cartilage
Enclosed within joint cavity by a fibrous
articular capsule & lubricate with synovial fluid
Usually freely movable [diarthrotic]
Types :
Hinge joint, Pivot joint, Condyloid joint,
Plane joint, Saddle joint, Ball and socket
joint
STRUCTURE OF
SYNOVIAL JOINTS
Articular cartilage
- Hyaline cartilage
covers the
surfaces
- Absorb compression
Joint / Synovial
cavity
- Joint cavity contains
synovial fluid for
lubrication
Articular capsule
- Consist of two layers : Fibrous capsule [outer]
: Synovial membrane
[inner]
Synovial fluid Reinforcing ligaments
- Occupies space -Thicken parts of
within the joint fibrous capsule
capsule - Supplied with nerve
- Reduce reduction
between cartilages endings and blood
vessels
TYPES OF MOVEMENTS
SINOVIAL JOINTS ALLOWED BY
- Nonaxial [gliding] SYNOVIAL JOINTS
[found between - Gliding movement
proximal end of ulna - Flexion
and radius] - Abduction
- Uniaxial - Adduction
[in one plane] - Opposition
[example : elbow
joint]
- biaxial
[in two planes]
[example : wrist]
- multiaxial
[in all three planes]
[example : hip joint
and shoulder]